Conjugated polymers (CPs) are efficient light-gathering molecules with properties desirable for a variety of applications. Conjugated polymers can serve as light harvesting materials and signal transducers in fluorescent biosensor applications.1,2 These molecules can detect, transduce and/or amplify chemical, biological or physical information into optical and/or electrical signals.3,4 CPs can provide the advantage of collective response relative to non-interacting small molecules.5,6 This collective response influences optoelectronic properties, such as Förster resonance energy transfer (FRET), electrical conductivity and fluorescence efficiency, properties which can be used to report, or “transduce,” target analyte presence.6 
Water solubility of CPs, a prerequisite for interrogating biological substrates, is usually achieved by charged groups attached to the CP backbone.7 To date, however, most of the available ionic conjugated polymers are polyanions containing sulfonate or carboxylate functionalities.
Conjugated polymers frequently take the form of rigid-rod structures which have limited flexibility and consequently have a limited ability to adapt to particular three dimensional shapes, thus limiting their ability to conform to the shape of biologically-derived molecules. For example, proteins and nucleic acids, although also polymeric, do not typically form extended-rod structures but rather fold into higher-order three-dimensional shapes to which CPs cannot typically conform.
All the currently available cationic water-soluble conjugated polymers have generally linear “rigid-rod” polymer backbones and therefore experience a limited twist angle between monomer units along the polymer main chain. A consequence of this torsional restriction is that the polymer has a “rigid rod” structure with limited conformations and ability to adapt to the secondary structures of bio-molecules. Additionally, when cationic conjugated polymers are used as light-harvesting molecules, they can deleteriously exhibit fluorescence self-quenching when they cluster near negatively charged biomolecules.
There is a need in the art for novel CCPs, for methods of making and using them, and for compositions and articles of manufacture comprising such compounds.